<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Demo3-9</title>
</head>
<body>
    <script src="/js/vue.js"></script>
    <div id="app">
       <p v-if="show">第一段文字</p>
       <p v-show="show">第二段文字</p>
    </div>
</body> 
    <script>
      let vm = new Vue({
        el:"#app",
        data:{ 
          show:true
        }
    })
    </script>
</html>